JPS60243814A - Magnetic characteristic measuring instrument of magnetic head - Google Patents

Abstract

PURPOSE:To evaluate and measure a magnetic head in a short time, by providing a magnetic head for measurement having tracks of the same number as the kind of magnetic tapes for measurement having different characteristics from each other. CONSTITUTION:The magnetic tape 18 for measurement of the magnetic characteristic measuring instrument of this invention uses three kinds of recording media C-E and the magnetic head for measurement 19 is three track type having tracks F, G, and H. When a sound recording head 1 to be measured is tested, simultaneous measurement is performed by passing each track of the magnetic head 19 for measurement through a reproducing system circuit. When an erase head 11 to be measured using a permanent magnet is tested, the magnetic head 19 for measurement is used as a sound recording head and reproducing head for measurement. Therefore, the time required for estimating and measuring a magnetic head can be reduced remarkably.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an apparatus for measuring magnetic characteristics of a magnetic head used mainly in tape recorders, set decks, cassette tape recorders with radios, etc. in the field of audio equipment.

A conventional test method for evaluating the dynamic characteristics of a recording head (including a recording head during recording) and an erasing head will be described with reference to FIGS. 1 to 4.

First, a method for testing a recording head will be explained with reference to FIG. 1. A recording current is applied to the recording head 1 to be measured by a bias oscillator 4 and a low frequency oscillator 5, recording is performed on a magnetic tape 10 for measurement, and a recording current is applied to the recording head 1 to be measured. Played by
An output voltage is obtained by a regenerative amplifier 7, a bandpass filter 8, and a level meter 9. These measurement procedures were used to measure the specified bias current, recording current, distortion rate, recording frequency characteristics, etc.

Next, a method for testing an erase head will be described using FIGS. 2 to 4. FIG. 2 is a circuit block diagram for measuring a specified erasing current, in which a recording current is applied to the measuring recording head 12, a specified level is recorded on the measuring magnetic tape 10, and an erasing oscillator is applied to the measuring recording head 2. An erase current was applied from 6, the reproduced output was obtained, and a specified erase current was charged. FIG. 3 is a circuit block diagram for testing the erase head 11 to be measured using a permanent magnet that does not require an erase current in place of the erase head 2 to be measured. FIG. 4 is a circuit block diagram for measuring the distortion rate and S/N of an erase head to be measured using a permanent magnet, which is an example of a DC type erase head. The recorded portion of the magnetic tape 10 is erased, and after erasing, a specified frequency and level are recorded using the measurement recording head 12, and the distortion rate is measured using the measurement playback head 3 and the bandpass filter 8.
Furthermore, the S
I was looking at /N. Note that a DC erase head to which a DC current is applied can also be used as the erase head to be measured.

FIG. 5 is an explanatory diagram of the measurement magnetic tape 10.

B is the recording side. Figure 6 shows the bottom 12 of the recording spatula for measurement.
Alternatively, in the front view of the measurement reproducing head 3, 13 is a magnetic helad core, 14 is a magnetic head gap, and 15 is a tape guide. Figure 7 is a front view of the erase head to be measured.
6 is a magnet part, and 17 is a part of a dummy.

That is, conventionally, one type of recording medium was used as the measuring magnetic tape 10, and the measuring recording head 12 or the measuring reproducing head 3 was placed below the tape center or i-p guide center. Those having one or two tracks were used.

The characteristics of the recording head and erasing head have been evaluated and tested using the above method. However, according to this conventional method, if the type of magnetic tape 10 for measurement changes, the tape must be replaced each time, or a different type of tape must be used. I had to reinstall it in the measurement system.

As a result, a great deal of time was spent evaluating and testing one head. Particularly in the case of premature birth, the number of measurements and inspections is extremely small, making it difficult to discover defective products.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional drawbacks, and aims to provide a method for measuring magnetic characteristics of a magnetic head [2] that allows evaluation and measurement of a magnetic head in a short time.

Structure of the Invention In order to achieve the above object, the magnetic head magnetic characteristic measuring device of the present invention has a structure including a measuring magnetic head having the same number of tracks as types of measuring magnetic tapes having mutually different magnetic characteristics. This is what I did.

DESCRIPTION OF THE EMBODIMENTS Hereinafter, one embodiment of the present invention will be briefly described with reference to the drawings.

FIG. 8 is an explanatory diagram of a measuring magnetic tape of a magnetic head magnetic characteristic measuring apparatus according to an embodiment of the present invention, FIG. 9 is a front view of the measuring magnetic head of the same magnetic characteristic measuring apparatus, and FIG. 10 is the same. FIGS. 11 and 12 are circuit block diagrams for testing a recording head using the magnetic property measuring device; FIGS. 11 and 12 are circuit block diagrams for testing a permanent magnet erase head using the magnetic property measuring device, respectively. , and Figure 1~
Components that are the same as those shown in FIG. 7 are given the same reference numerals, and their explanations will be omitted.

As shown in FIG. 8, the measurement magnetic chip 718 uses three types of recording media C-E, and the recording medium C is γ-Fe.
2O3 (normal), recording medium contains CO-Fe2
03 (chromium), and the recording medium E is Fe (metal).

The measuring magnetic head 19 is of a three-track type having tracks F, G, and H, as shown in FIG.

When testing the recording head 1 to be measured, as shown in FIG. 10, simultaneous measurements are made for each track of the measuring magnetic head 19 through the reproduction circuit. This reduced the measurement time to less than 1/7 of the conventional measurement time.

When testing the erase head 11 to be measured using a permanent magnet, as shown in FIG. 11, the measuring magnetic head 19 is used as a recording head and a reproducing head for measurement. This made it possible to shorten the measurement time to 1/8 or less compared to the conventional method.

FIG. 12 is a circuit block diagram of Yang Kai, which further adds a measurement magnetic head 19 to the circuit shown in FIG. 11 to measure the erasure rate at the same time.
I was able to shorten it to less than 10.

In the above embodiment, the case of three tracks has been explained, but it goes without saying that sufficient effects can be obtained also in the case of two or four or more tracks.

Furthermore, in the above embodiment, an example was explained in which multiple types of recording media C-E were used as the magnetic tape 718 for measurement, but the present invention uses multiple types of magnetic tape 10 for measurement using recording media of class 111. Of course, it is effective even when

Effects of the Invention As explained above, according to the present invention, the time required for evaluating and measuring magnetic heads can be drastically reduced, and its industrial utility value is extremely large.

[Brief explanation of the drawing]

Figures 1 to 7 show conventional examples, Figure 1 is a circuit block diagram for testing and measuring a recording head, Figure 2 is a circuit block diagram for testing and measuring an AC erase head, and Figure 3 is a circuit block diagram for testing and measuring an AC erase head.
The figure is a circuit block diagram for testing and measuring the erasure rate of a permanent magnet erase head, Figure 4 is a circuit block diagram for testing and measuring the distortion rate and S/N of a permanent magnet erase head, and Figure 5 is a circuit block diagram for testing and measuring the erasure rate of a permanent magnet erase head. An explanatory diagram of a non-recording tape for measurement, FIG. 6 is a front view of a recording head for measurement or an erasing head for measurement, FIG. 7 is a front view of a permanent magnet erasing head, and FIGS. 8 is an explanatory diagram of a non-recording tape for measurement, FIG. 9 is a front view of a recording/playback head for measurement, and FIG.
FIG. 0 is a circuit block diagram for testing and measuring an anastomotic head, and FIGS. 11 and 12 are circuit block diagrams for testing and measuring a permanent vi1 stone-shaped erase head, respectively. 10, 18... Magnetic tape for measurement, 19... Magnetic head representative for measurement Yoshihiro Morimoto Figure 1 q β 7 Figure 2 Figure 4 Figure 5 Figure 6 Figure 7 Figure 1 Fig. 2 Fig. 9 Fig. 1θ Fig. IT Fig. 12

Claims (1)

[Claims] 1.! (i) A magnetic characteristic measuring device for a magnetic head, comprising a measuring magnetic head having the same number of tracks as types of measuring magnetic tapes having different magnetic characteristics. 2.1! 2. The apparatus for measuring magnetic properties of a magnetic head according to claim 1, wherein the magnetic tape for determining the IQ has a structure in which a plurality of recording media having different magnetic properties are divided and arranged in the width direction of the tape.